Chile has extended a state of emergency to cities in the country's north and south amid an "escalation of violence and vandalism."
Officials said five people died when a garment factory was torched in a suburb north of Santiago, bringing the death toll in a wave of unrest in Chile to seven.
"We are at war against a powerful enemy, who is willing to use violence without any limits," President Sebastian Pinera said in a late-night televised statement at army headquarters in Santiago.
"I call on all my compatriots to unite in this battle against violence and delinquency."
Protests led by students began two weeks ago over fare hikes on public transport.

US, Iran inch closer to deal, timing remains unclear
Sirens sound in Jordan due to technical malfunction, state TV reports
India Air Force plane crash kills all five onboard
Ukrainian strike kills one, wounds 3 in southern Russia
Trump says US military strike killed leader of Venezuela's Tren de Aragua gang
Qatar rejects media report on energy production decisions
Trump says Iran war deal close as Strait of Hormuz tensions linger
Victims' families mark Air India crash anniversary with prayers and tributes
